New research by the Health Education Authority reveals big gaps in teenagers' knowledge about sex. One in six 15-year-old boys say they have heard of "gonaditis", a non-existent sexually transmitted disease made up by researchers.
But fewer have heard of chlamydia, a real disease that can make women infertile.
Ministers are reconsidering sex education as part of a wide-ranging review of the curriculum, which includes citizenship, moral and spiritual values and the arts, as well as academic subjects. The results are expected to be announced next month.
The latest research into young people's attitudes and behaviour, Young People and Health, was carried out among 10,407 11 to 16-year-olds in 70 English secondary schools. They were questioned about school, family life, smoking, drinking, drug-taking and sexual health.
Although three-quarters of children like school, bullying is widespread. Half of all children have been bullied at school at some time and one in five said they had been the victims of bullying during the current term.
Children who are bullied tend to bully others - about 40 per cent of the victims admitted they were also bullies. Sixteen per cent have been made fun of because of their race and religion.
When they were questioned about sex education, nearly all recalled lessons about the development of the body, sexual relationships, contraception and birth control.
However, teenagers would like more information about homosexuality and lesbianism. Fifteen and 16-year-olds would also like more information about Aids. More teenagers - 92 per cent - know about HIV/Aids than other sexually transmitted diseases, the survey shows.
Only 39 per cent have heard of gonorrhoea, 33 per cent of syphilis and 51 per cent of herpes. Reports of gonorrhoea among 16 to 19-year-olds rose 46 per cent between 1995 and 1997. For chlamydia, the figure was 56 per cent. Nine out of 10 young people had heard of the condom and the contraceptive pill.
Neither drug taking nor drinking appears to be increasing. Both are at about the same level as they were three years ago. Alcopops are growing in popularity.
Twenty per cent do not drink at all and three-fifths drink only a little. Five per cent of children are already drinking at the age of 11, compared with nearly half of 16-year-olds.
Children who dislike school are more likely to take risks with their health such as smoking, drinking and taking drugs.Reuse content